Activated memory B cells may function as antigen-presenting cells in the joints of children with juvenile idiopathic arthritis.

Objective: B cells impact the perpetuation of chronic inflammatory or autoimmune diseases in multiple ways. A role of B cells as antigen-presenting cells (APCs) in the pathogenesis of chronic arthritis in humans has been suggested; however, as of yet the presence of such B cells at the site of inflammation has not been demonstrated. This study was undertaken to investigate whether synovial B cells in patients with juvenile idiopathic arthritis (JIA) might display features of APCs.

The kappa immunoglobulin light chain repertoire of peripheral blood B cells in patients with juvenile rheumatoid arthritis.

The frequent appearance of antinuclear antibodies in patients with juvenile rheumatoid arthritis (JRA) indicates a loss of tolerance in B cell differentiation and/or activation. In this analysis, we were interested whether particular changes in the immunoglobulin light chain repertoire might exist in early-onset pauciarticular arthritis (EOPA) patients thereby potentially revealing distinct molecular patterns, which characterize defects in central tolerance mechanisms as well as an autoreactive peripheral B cell repertoire. Using single cell sorting and single cell PCR the distribution of Vkappa Jkappa rearrangements has been analyzed in individual naïve B cells of patients with EOPA-JRA and healthy individuals.

Seasonal and habitat-related distribution pattern of Synechococcus genotypes in Lake Constance.

The abundance and distribution of Synechococcus spp. in the autotrophic picoplankton of Lake Constance, were followed in the pelagic and littoral habitat by qPCR over 2 years. One genotype, represented by isolated phycoerythrin-rich strain BO 8807, showed a seasonal distribution pattern in both habitats.